Fort Denison is a popular tourist attraction located in Sydney Harbour just north of Woolloomooloo Bay. It is a much-coveted location for weddings, festivals and other events. The Fort Denison Café and Restaurant features brunch, fresh seafood and kid-friendly menus for its guests. Fort Denison provides its visitors an opportunity to study the maritime and colonial history of the area and a lovely view of the harbour.

Once called Muttewai by the Aboriginals, the small, rocky island was renamed Rock Island in 1788 by Governor Phillip. Rock Island was used for solitary confinement for unruly convicts. The first sent there was a convict who had been caught stealing biscuits. Because convicts who were sent there were given only bread and water for the duration of their sentencing, the locals were more apt to call the island Pinchgut.

The sandstone rocks of Rock Island were quarried to build Bennelong Point, which later became the foundation of the Sydney Opera House. The island, which was now flat, was fortified, and in 1857, a tower was added to guard Sydney against attacks. It was renamed Fort Denison after the then-governor of New South Wales, Sir William Thomas Denison. The cannons of Fort Denison have never been fired in defence.

The Naval Brigade managed Fort Denison as a fortress until 1869, and the Sydney Harbour Trust took over from 1900 until 1992. Although pranks rarely make it into the annals of history, Fort Denison is associated with one particularly well-known prank, which occurred. During the Boer War, an officer named Charles Lightoller, who would later become a survivor of the Titanic and a key witness in related inquests, charged and fired antiquated ordnance at the fort. He and his associates painted a piece of cloth to resemble the Boer flag and affixed it to the tower. Lightoller was officially reprimanded for his role in the stunt.

In 1992, the NSW National Parks & Wildlife Service took over the management of Fort Denison. Today, Fort Denison is a major tourist destination that allows visitors to explore the history of the area or simply enjoy a relaxing day out. It features a Martello tower, landmarks and a museum displaying colonial artefacts and a comprehensive history of the fort.

Guided tours of Fort Denison are available every 30 minutes, and self-guided tours are welcomed during regular park hours. Fort Denison can be reached easily by taking a water taxi or ferry, both of which run from Darling Harbour and Circular Quay daily every 45 minutes between 10a.m. and 3:50 p.m. The Hop On Hop Off Day Pass also stops at Fort Denison as well as Luna Park, Taronga Zoo, Watsons Bay, Circular Quay and Darling Harbour. The fort is not wheelchair or pram accessible.